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jonny [76]
3 years ago
8

Can anyone help me with this last question?

Physics
1 answer:
Digiron [165]3 years ago
6 0

Answer:

v = 39.6 m/s (first answer option)

Explanation:

Use conservation of mechanical energy.

The starting is completely potential energy and the final is all kinetic energy:

m*g*h=\frac{1}{2}*m*v^2\\g *  h=\frac{1}{2} v^2\\9.8*80=\frac{1}{2} v^2\\v^2=1568\\v\approx 39.6\,\,m/s

which agrees with the first answer shown.

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Inductors in parallel. Two inductors L1 = 1.31 H and L2 = 2.24 H are connected in parallel and separated by a large distance so
mote1985 [20]

Answer:

a) 0.83H

b) 3.22/N Henry

Explanation:

Given two inductors L1 = 1.31 H and L2 = 2.24 H connected in parallel, their equivalent inductance derivative is similar to that of resistance in parallel.

Derivation:

If the voltage across an inductor

VL = IXL

I is the current

XL is the inductive reactance

XL = 2πfL

VL = I(2πfL)

L is the inductance.

From the formula, I = V/2πfL

Given two inductors in parallel, different current will flow through them.

I1 = V/2πfL1 (current in L1)

I2 = V/2πfL2 (current in L2)

Total current I = I1+I2

I = V/2πfL1 + V/2πfL2

I = V/2πf{1/L1+1/L2}

V/2πfL = V/2πf{1/L1+1/L2}

1/L = 1/L1+1/L2 (equivalent inductance in parallel)

Given L1 = 1.31 H and L2 = 2.24

1/L = 1/1.31 + 1/2.24

1/L = 0.763 + 0.446

1/L = 1.209

L = 1/1.209

L = 0.83H

The equivalent inductance is 0.83H

b) Given similar inductors L = 3.22H in parallel, the equivalent inductance will be:

1/L = 1/3.22+1/3.22+1/3.22+1/3.22+1/3.22

+1/3.22+1/3.22+1/3.22+1/3.22+1/3.22

1/L = 10/3.22 (since that all have the same denominator)

L = 3.22/10

If N = 10, the generalization of 10 similar inductors in parallel will be:

L = 3.22/N Henry

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3 years ago
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ch4aika [34]

Answer:  

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Hope this helps :)

4 0
3 years ago
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In a closed energy system, energy is?​
Alisiya [41]

Answer:

Explanation:

A closed system can exchange energy but not matter, with its surroundings. An isolated system cannot exchange any heat, work, or matter with the surroundings, while an open system can exchange energy and matter.

Hope this helped you!

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2 years ago
Need help with exercises 3,4,5<br><br> Will give brainliest!!!
Harman [31]

I pretty sure that 3 is b and 4 is A and 5 I need a full picture

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What is it about copper that makes it a good conductor
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